[5.10,08/10] KVM: X86: Ensure that dirty PDPTRs are loaded

Message ID	20230508154804.30078-9-minipli@grsecurity.net (mailing list archive)
State	New, archived
Headers	show Return-Path: <kvm-owner@vger.kernel.org> From: Mathias Krause <minipli@grsecurity.net> To: stable@vger.kernel.org Cc: Paolo Bonzini <pbonzini@redhat.com>, Sean Christopherson <seanjc@google.com>, kvm@vger.kernel.org, Mathias Krause <minipli@grsecurity.net>, Lai Jiangshan <laijs@linux.alibaba.com> Subject: [PATCH 5.10 08/10] KVM: X86: Ensure that dirty PDPTRs are loaded Date: Mon, 8 May 2023 17:48:02 +0200 Message-Id: <20230508154804.30078-9-minipli@grsecurity.net> In-Reply-To: <20230508154804.30078-1-minipli@grsecurity.net> References: <20230508154804.30078-1-minipli@grsecurity.net> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk
Series	KVM CR0.WP series backport \| expand [5.10,00/10] KVM CR0.WP series backport [5.10,01/10] KVM: x86/mmu: Avoid indirect call for get_cr3 [5.10,02/10] KVM: x86: Do not unload MMU roots when only toggling CR0.WP with TDP enabled [5.10,03/10] KVM: x86: Make use of kvm_read_cr*_bits() when testing bits [5.10,04/10] KVM: VMX: Make CR0.WP a guest owned bit [5.10,05/10] KVM: x86: Read and pass all CR0/CR4 role bits to shadow MMU helper [5.10,06/10] KVM: X86: Don't reset mmu context when X86_CR4_PCIDE 1->0 [5.10,07/10] KVM: X86: Don't reset mmu context when toggling X86_CR4_PGE [5.10,08/10] KVM: X86: Ensure that dirty PDPTRs are loaded [5.10,09/10] KVM: x86/mmu: Reconstruct shadow page root if the guest PDPTEs is changed [5.10,10/10] KVM: x86/mmu: Refresh CR0.WP prior to checking for emulated permission faults

Message ID

20230508154804.30078-9-minipli@grsecurity.net (mailing list archive)

State

New, archived

Headers

From: Mathias Krause <minipli@grsecurity.net>
To: stable@vger.kernel.org
Cc: Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <seanjc@google.com>, kvm@vger.kernel.org,
        Mathias Krause <minipli@grsecurity.net>,
        Lai Jiangshan <laijs@linux.alibaba.com>
Subject: [PATCH 5.10 08/10] KVM: X86: Ensure that dirty PDPTRs are loaded
Date: Mon,  8 May 2023 17:48:02 +0200
Message-Id: <20230508154804.30078-9-minipli@grsecurity.net>
In-Reply-To: <20230508154804.30078-1-minipli@grsecurity.net>
References: <20230508154804.30078-1-minipli@grsecurity.net>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Series

KVM CR0.WP series backport | expand

Commit Message

Mathias Krause May 8, 2023, 3:48 p.m. UTC

From: Lai Jiangshan <laijs@linux.alibaba.com>

[ Upstream commit 2c5653caecc4807b8abfe9c41880ac38417be7bf ]

For VMX with EPT, dirty PDPTRs need to be loaded before the next vmentry
via vmx_load_mmu_pgd()

But not all paths that call load_pdptrs() will cause vmx_load_mmu_pgd()
to be invoked.  Normally, kvm_mmu_reset_context() is used to cause
KVM_REQ_LOAD_MMU_PGD, but sometimes it is skipped:

* commit d81135a57aa6("KVM: x86: do not reset mmu if CR0.CD and
CR0.NW are changed") skips kvm_mmu_reset_context() after load_pdptrs()
when changing CR0.CD and CR0.NW.

* commit 21823fbda552("KVM: x86: Invalidate all PGDs for the current
PCID on MOV CR3 w/ flush") skips KVM_REQ_LOAD_MMU_PGD after
load_pdptrs() when rewriting the CR3 with the same value.

* commit a91a7c709600("KVM: X86: Don't reset mmu context when
toggling X86_CR4_PGE") skips kvm_mmu_reset_context() after
load_pdptrs() when changing CR4.PGE.

Fixes: d81135a57aa6 ("KVM: x86: do not reset mmu if CR0.CD and CR0.NW are changed")
Fixes: 21823fbda552 ("KVM: x86: Invalidate all PGDs for the current PCID on MOV CR3 w/ flush")
Fixes: a91a7c709600 ("KVM: X86: Don't reset mmu context when toggling X86_CR4_PGE")
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Message-Id: <20211108124407.12187-2-jiangshanlai@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Mathias Krause <minipli@grsecurity.net>	# backport to v5.10.x
---
 arch/x86/kvm/x86.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index b2378ec80305..038ac5bbdd19 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -794,6 +794,7 @@  int load_pdptrs(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu, unsigned long cr3)
 
 	memcpy(mmu->pdptrs, pdpte, sizeof(mmu->pdptrs));
 	kvm_register_mark_dirty(vcpu, VCPU_EXREG_PDPTR);
+	kvm_make_request(KVM_REQ_LOAD_MMU_PGD, vcpu);
 
 out:

[5.10,08/10] KVM: X86: Ensure that dirty PDPTRs are loaded

Commit Message

Patch